Selective Separation of Indium and Germanium from Leaching Solutions Using Membrane Technology

The increasing demand for the strategic elements indium and germanium necessitates the development of new extraction methods. The goal of the presented study is the development of a sustainable method for the selective recovery of indium and germanium from leaching solutions within a bioleaching process. Rather than commonly used solvent extraction the application of membrane technology, in particular nanofiltration and supported liquid membrane, has been investigated. Results with nanofiltration show that indium and germanium can be separated selectively depending on the pH value of the solution. Furthermore, extraction of indium from a concentrated solution containing Zn, Cu, Fe, and As using supported liquid membrane was performed successfully.